A maximum of 1% of people with the flu get tested because most tests need trained staff and expensive equipment. Researchers from the Broad Institute, MIT, Harvard, and Princeton, supported by the CDC, developed a low-cost paper strip test using CRISPR. This test can identify flu types A and B, subtypes H1N1 and H3N2, and strains resistant to treatment. With further development, it could also detect swine and avian flu strains.
Published in The Journal of Molecular Diagnostics, the study’s results could improve outbreak response and clinical care by providing accurate, low-cost, and fast tests to doctors and labs worldwide.
Co-senior authors Cameron Myhrvold and Pardis Sabeti hope these tests will be as simple as rapid antigen tests but with the accuracy of lab-based nucleic acid tests. Myhrvold, now a Princeton assistant professor, began the study as a postdoctoral researcher in Sabeti’s lab.
The test uses SHINE technology, developed by Sabeti’s lab in 2020, which employs CRISPR enzymes to identify viral RNA in samples. Initially, SHINE tested for SARS-CoV-2 and later differentiated between Delta and Omicron variants.
In 2022, researchers adapted it to detect flu viruses, aiming for use in the field or clinics without expensive equipment. Ben Zhang, the co-first author, highlighted the paper strip readout as a significant advancement for clinical care and epidemiological surveillance.
Typical diagnostic methods like PCR require long processing times, trained staff, special equipment, and storage of reagents at 80 °C. In contrast, SHINE works at room temperature for about 90 minutes and only needs a cheap heat block. Researchers aim to reduce the time to 15 minutes. They have also adapted SHINE to identify different flu strains and hope to use it to detect viruses with similar symptoms, like flu and COVID-19, in the future.
“Identifying the specific strain or subtype of influenza affecting a patient is crucial for treatment and public health,” said Jon Arizti-Sanz, a postdoctoral researcher and co-first author of the study.
This information can guide clinicians on using Oseltamivir, an antiviral effective only for specific strains. Rapid tests also help scientists monitor outbreaks more effectively. The researchers are now adapting SHINE to detect avian and swine flu strains like H5N1.
Journal reference:
- Yibin B. Zhang, Jon Arizti-Sanz, et al., CRISPR-Based Assays for Point-of-Need Detection and Subtyping of Influenza. The Journal of Molecular Biology. DOI: 10.1016/j.jmoldx.2024.04.004.
